diff options
| author | Damien Lespiau <damien.lespiau@intel.com> | 2012-12-11 18:48:29 +0000 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-02-20 00:21:45 +0100 |
| commit | 3e68320ef84528604d971afc3cadfbe208bef001 (patch) | |
| tree | 8218fb517cca5f9b64dbd6bbef9eccf0aba084a2 /drivers/gpu/drm/i915/intel_crt.c | |
| parent | fdfa175d0a9cfa2082ce24e67e284e5acbba452a (diff) | |
drm/i915: Preserve the FDI line reversal override bit on CPT
The FDI link has supported link reversal to make the PCB layout
engineer's life easier for quite a while and we have always presered
this bit as we programmed FDI_RX_CTL with a read/modify/write sequence.
We're trying to take a bit more control over what the BIOS leaves in
various register and with the introduction of DDI, started to program
FDI_RX_CTL fully.
There's a fused bit to indicate DMI link reversal and FDI defaults to
mirroring that configuration. We have a bit to override that behaviour
that we need to preserve from the BIOS.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_crt.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_crt.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index 68e79f32e10..cfc96878d74 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -801,10 +801,14 @@ void intel_crt_init(struct drm_device *dev) dev_priv->hotplug_supported_mask |= CRT_HOTPLUG_INT_STATUS; /* - * TODO: find a proper way to discover whether we need to set the - * polarity reversal bit or not, instead of relying on the BIOS. + * TODO: find a proper way to discover whether we need to set the the + * polarity and link reversal bits or not, instead of relying on the + * BIOS. */ - if (HAS_PCH_LPT(dev)) - dev_priv->fdi_rx_polarity_reversed = - !!(I915_READ(_FDI_RXA_CTL) & FDI_RX_POLARITY_REVERSED_LPT); + if (HAS_PCH_LPT(dev)) { + u32 fdi_config = FDI_RX_POLARITY_REVERSED_LPT | + FDI_RX_LINK_REVERSAL_OVERRIDE; + + dev_priv->fdi_rx_config = I915_READ(_FDI_RXA_CTL) & fdi_config; + } } |